#include "stm32f1xx_hal.h"
#include "stm32f1xx_hal_tim.h"

TIM_HandleTypeDef htim4;
void TIM4_IRQHandler(void);

HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority) {
    RCC_ClkInitTypeDef clkconfig;
    uint32_t uwTimclock, uwAPB1Prescaler = 0U;

    uint32_t uwPrescalerValue = 0U;
    uint32_t pFLatency;
    HAL_StatusTypeDef status = HAL_OK;

    /* Enable TIM4 clock */
    __HAL_RCC_TIM4_CLK_ENABLE();

    /* Get clock configuration */
    HAL_RCC_GetClockConfig(&clkconfig, &pFLatency);

    /* Get APB1 prescaler */
    uwAPB1Prescaler = clkconfig.APB1CLKDivider;
    /* Compute TIM4 clock */
    if (uwAPB1Prescaler == RCC_HCLK_DIV1) {
        uwTimclock = HAL_RCC_GetPCLK1Freq();
    } else {
        uwTimclock = 2UL * HAL_RCC_GetPCLK1Freq();
    }

    /* Compute the prescaler value to have TIM4 counter clock equal to 1MHz */
    uwPrescalerValue = (uint32_t)((uwTimclock / 1000000U) - 1U);

    /* Initialize TIM4 */
    htim4.Instance = TIM4;

    /* Initialize TIMx peripheral as follow:

    + Period = [(TIM4CLK/1000) - 1]. to have a (1/1000) s time base.
    + Prescaler = (uwTimclock/1000000 - 1) to have a 1MHz counter clock.
    + ClockDivision = 0
    + Counter direction = Up
    */
    htim4.Init.Period = (1000000U / 1000U) - 1U;
    htim4.Init.Prescaler = uwPrescalerValue;
    htim4.Init.ClockDivision = 0;
    htim4.Init.CounterMode = TIM_COUNTERMODE_UP;
    htim4.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;

    status = HAL_TIM_Base_Init(&htim4);
    if (status == HAL_OK) {
        /* Start the TIM time Base generation in interrupt mode */
        status = HAL_TIM_Base_Start_IT(&htim4);
        if (status == HAL_OK) {
            /* Enable the TIM4 global Interrupt */
            HAL_NVIC_EnableIRQ(TIM4_IRQn);
            /* Configure the SysTick IRQ priority */
            if (TickPriority < (1UL << __NVIC_PRIO_BITS)) {
                /* Configure the TIM IRQ priority */
                HAL_NVIC_SetPriority(TIM4_IRQn, TickPriority, 0U);
                uwTickPrio = TickPriority;
            } else {
                status = HAL_ERROR;
            }
        }
    }

    /* Return function status */
    return status;
}

/**
 * @brief  Suspend Tick increment.
 * @note   Disable the tick increment by disabling TIM4 update interrupt.
 * @param  None
 * @retval None
 */
void HAL_SuspendTick(void) {
    /* Disable TIM4 update Interrupt */
    __HAL_TIM_DISABLE_IT(&htim4, TIM_IT_UPDATE);
}

/**
 * @brief  Resume Tick increment.
 * @note   Enable the tick increment by Enabling TIM4 update interrupt.
 * @param  None
 * @retval None
 */
void HAL_ResumeTick(void) {
    /* Enable TIM4 Update interrupt */
    __HAL_TIM_ENABLE_IT(&htim4, TIM_IT_UPDATE);
}
